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Catmur C, Walsh V, Heyes C.Catmur C, et al.Philos Trans R Soc Lond B Biol Sci. 2009 Aug 27;364(1528):2369-80. doi: 10.1098/rstb.2009.0048.Philos Trans R Soc Lond B Biol Sci. 2009.PMID: 19620108Free PMC article.Review.